Refrigerating apparatus



J. R. KILLEN REFRIGERATING APPARATUS Filed Oct. 30, 1933 July 30, 1935.

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ATTORN S Patented July 30, 1935 UNITED STATES REFRIGERATING APPARATUS James R. Killen, Dayton, Ohio, assignor to General Motors Corporation, Dayton, Ohio, a corporation of Delaware Application October 30,

6 Claims.

This invention relates to refrigeration apparatus and more particularly to refrigerating apparatus for cooling water, beverages and the like.

In an apparatus for cooling beverages, and particularly beer, a pipe or conduit is generally provided, through which the beer flows prior to its discharge at the faucet. This pipe is refrigerated by liquid refrigerant of a refrigerating system in which refrigerant the pipe is submerged or with which it is otherwise in thermal contact. In such apparatus it is generally desirable to clean the interior of the conduit or pipe periodically by running steam or other hot cleansing fluid through the pipe. Under such conditions, abnormal and dangerous high pressures are likely to be created in the refrigerating system because of the rapid evaporation of large quantities of refrigerant. Means are therefore provided for moving the liquid refrigerant out of contact with the pipe or conduit during the cleaning operation. In this invention, improved and simplified means are provided for accomplishing this result.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawing, wherein a preferred form of the present invention is clearly shown.

In the drawing:

Fig. 1 is a view, partly diagrammatic and partly in cross section, of an apparatus embodying features of my invention;

Fig. 2 is a partial view of a slightly modified form of a portion of the apparatus; and

Fig. 3 is a cross sectional view of a portion of a check valve suitable for use in the apparatus.

A refrigerating apparatus embodying features of my invention includes in general, a com pressor 0, a condenser I I, which is provided with a receiver I2, and a refrigerant evaporator I3. The compressor, condenser and evaporator are placed in closed refrigerant circuit relationship, and this is accomplished by providing a pipe or connection I4 between the condenser and the evaporator for normal flow of liquid refrigerant from the condenser to the evaporator, and by providing an evaporated refrigerant line or pipe I5 for normal flow of evaporated refrigerant from the evaporator to the compressor. The compressor I0 discharges compressed refrigerant to the condenser through the pipe I6. Means are provided for maintaining a body of liquid refrigerant in the evaporator. In this particular embodiment, a float controlled valve I1 is placed in the evaporator I3 and this controls the flow 1933, Serial No. 695,809

of refrigerant through the pipe I4 and maintains a substantially constant level I8 of liquid refrigerant in the evaporator I3. Any suitable type of refrigerating system may be used in the embodiment of the invention described thus far.

A conduit for liquid to be cooled is placed in thermal exchange relation with the evaporator. In this particular embodiment, a pipe I9 is submerged in the body I8 of refrigerant. This pipe I9 is connected at one end with the source of supply liquid, such as a barrel 20, and at the other end is connected to a faucet 2|. The barrel 2!) is placed under CO2 pressure through the pipe 22 in the usual manner which includes a C02 pressure driven and automatic pressure, reducing valve, not shown, and when the faucet 2| is opened beer flows through the pipe I9 and is cooled to the desired temperature.

It is desirable that the system operate automatically so that the body of liquid refrigerant I8 is maintained at a substantially constant temperature regardless of the demands placed on the system. To this end, the compressor I0 is driven by an electric motor 23, and the starting and stopping of the motor is governed by means of a snap switch 24 operated by a bellows 25 which is responsive to refrigerant pressures in pipe I5 and therefore responsive to the temperatures of the liquid refrigerant in the evaporator I3.

When the pipe I9 is to be cleaned, by passing steam or other hot fluid therethrough, the valve 26 is closed, and the steam or cleaning connection valve 21 is opened together with the valve 2|. When this is done the hot fluid flows through pipe I9. Under such circumstances, it is desirable that the liquid refrigerant in the evaporator I3 should be automatically removed, at least below the main body of the pipe I9. To this end, a connection or pipe 29 is placed with one end near the bottom of the body of liquid refrigerant in the evaporator I3, and preferably below the level of the main body of the pipe I9. The other end of the pipe 29 is connected with the condenser, preferably with the receiver I2 and near the bottom thereof. This may be accomplished by a separate pipe as shown in Fig. 1; or merely by connecting the pipe 29 by means of a by-pass 30 with the usual liquid line I4 which is connected with the intake of the evaporator. The pipe 29 is provided with a check valve 3|, which check valve prevents the flow of liquid refrigerant from the condenser to the evaporator through the check valve under nor mal conditions when the refrigerant pressure in the condenser is greater than in the evaporator,

but permits the flow of refrigerant from the evaporator to the condenser if the pressure in the evaporator should become great enough merely to overcome the small spring resistance of the check valve. A suitable check valve is shown in Fig. 3 wherein the plate 32 is urged against the valve seat 33 by a weak spring 34 held in place by the spider 35. When the hot cleaning fluid is introduced into the pipe IS, the liquid refrigerant l8 starts to boil violently, and soon the pressure in the evaporator l3 rises to the point where the check valve 3| opens and drains the evaporator l3 below the main body of the pipe l9. When this happens, liquid refrigerant does not enter through the valve I'l into the evaporator, because the pressure in the evaporator I3 is greater than in the condenser II. Thus, during the cleaningoperation, the liquid refrigerant is removed from the evaporator l3 sufficiently to prevent undue pressures in the refrigerating system.

It is to be understood that the difference in elevation between'the evaporator and the condenser may create a relatively large hydrostatic head in the liquid refrigerant lines, and that under such conditions, the pressures at the check valve itself governs its action. It is to be understood that where the claims define refrigerant pressures in the evaporator and condenser the hydrostatic head of the liquid refrigerant on either side of the check valve is to be included.

While the form of embodiment of the invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. In a refrigerating system, a compressor, condenser and evaporator in closed refrigerant circuit relationship, a refrigerant flow connection between said condenser and evaporator, means for normally maintaining a body of liquid refrigerant in said evaporator, a connection between the lower portion of said body of liquid refrigerant and said condenser and having a check valve preventing flow of refrigerant from said condenser to said evaporator through said check valve, and a conduit for liquid to be cooled in thermal exchange relation with the body of liquid refrigerant in said evaporator.

2. In a refrigerating system, a compressor, condenser and evaporator in closed refrigerant circuit relationship, a refrigerant flow connection between said condenser and evaporator, means for normally maintaining a body of liquid refrigerant in said evaporator, a connection between the lower portion of said body of liquid refrigerant and said condenser having means for permitting flow of liquid refrigerant from said evaporator to said condenser when refrigerant pressure is greater in said evaporator than in said condenser, and for preventing flow of liquid refrigerant from said condenser to said evaporator when refrigerant pressure is greater in said condenser than in said evaporator, and a conduit for liquid to be cooled in thermal exchange relation with the body of liquid refrigerant in said evaporator.

3. In a refrigerating system, a compressor, condenser and evaporator in closed refrigerant circuit relationship, a refrigerant flow connection between said condenser and evaporator, means for maintaining a body of liquid refrigerant in said evaporator when refrigerant pressure is greater in said condenser than in said evaporator,

and for returning liquid refrigerant from said evaporator to said condenser without the aid of said compressor when refrigerant pressure is greater in said evaporator than in said condenser, and a conduit for liquid to be cooled in thermal exchange relation with the body of liquid refrigerant in said evaporator.

4. In a refrigerating system, a compressor, condenser and evaporator in closed refrigerant circuit relationship, a refrigerant flow connection between said condenser and evaporator, means for normally maintaining a body of liquid refrigerant in said evaporator, and a connection between the lower portion of said body of liquid refrigerant and said condenser and having a check valve preventing flow of refrigerant from said condenser to said evaporator through said check valve.

5. In a refrigerating system, a compressor, condenser and evaporator in closed refrigerant circuit relationship, a refrigerant flow connection between said condenser and evaporator, means for normally maintaining a body of liquid refrigerant in said evaporator, and a connection between the lower portion of said body of liquid refrigerant and said condenser having means for permitting flow of liquid refrigerant from said evaporator to said condenser when refrigerant pressure is greater in said evaporator than in said condenser, and for preventing flow of liquid refrigerant from said condenser to said evaporator when refrigerant pressure is greater in said condenser than in said evaporator.

6. In a refrigerating system, a compressor, condenser and evaporator in closed refrigerant circuit relationship, a refrigerant flow connection between said condenser and evaporator, and means for maintaining a body of liquid refrigerant in said evaporator when refrigerant pressure is greater in said condenser than in said evaporator, and for returning liquid refrigerant from said evaporator to said condenser without the aid of said compressor when refrigerant pressure is greater in said evaporator than in said condenser.

JAMES R. KILLEN. 

